#20 - Concept Reference, Weaken

[Administrator]

Complete Question Explanation

The correct answer choice is (D).

Answer choice (A):

Answer choice (B):

Answer choice (C):

Answer choice (D): This is the correct answer choice.

Answer choice (E):


This explanation is still in progress. Please post any questions below!

[alicechoi86@gmail.com]

I'm confused on this one. I chose (B) because it says that the altered bacteria "can cause damage to crops" - wouldn't this weaken the proponents' claim of safety of using the altered bacteria?

From what I can tell, (D) [the correct answer] similarly suggests that altering genes often results in removing a gene that is required in order to prevent other harmful characteristics.

I thought about the strength of each to see which one "most seriously weakens." But I'm coming up with "can" in (B) and "often" in (D) - both of which suggest possibility and not certainty, so similarly not strong.

Could it be that (D) is stronger b/c it's talking about genes and (B) is talking about the strain of bacteria? In this case, I feel like my outside knowledge of biology is limited and that I would not have caught this distinction.

Curious to hear about what the distinction btwn (B) and (D) in this case is.

[evelineliu]

Hi Alice,

(B) is completely consistent with the proponents' argument, so it does not weaken their argument. They never claimed that the altered bacteria derived from anything but a harmful phytopathogen. Their claim is that they're turning a harmful bacterium into a beneficial one by altering its genetic structure.

The proponents claim that the new bacteria (old minus the one harmful gene) limits frost damage without causing any harmful effects. If it were true that the deletion of one gene could indeed cause harmful effects, this argument would be weakened. This makes (D) correct because if the gene removed from the original pathogenic bacteria may be responsible for protecting the crop in other ways, then removing the gene may endanger the crop and warrant the opponents' fear of "deleterious results."

Best,
Eveline